RENO, NEV. — Saline amnioinfusion for labors with thickly meconium-stained amniotic fluid does not prevent meconium aspiration syndrome, William D. Fraser, M.D., said at the annual meeting of the Society for Maternal-Fetal Medicine.
In an international, randomized, prospective trial of laboring women with thickly stained fluid, there was a 4% rate of moderate or severe meconium aspiration syndrome or death in 985 neonates born after amnioinfusion, compared with a 3% rate in 988 neonates born to women who did not undergo the procedure, said Dr. Fraser of the University of Montreal.
“Our evidence does not support amnioinfusion,” Dr. Fraser said.
The findings of the current study run counter to those of some previous studies, including a recent metaanalysis of 12 trials, which concluded that the practice reduces by two-thirds the rate of meconium aspiration syndrome.
The metaanalysis, however, was dominated by a single study conducted in Zimbabwe, where modern labor and delivery practices usually aren't implemented, Dr. Fraser said, adding that the other studies that showed a positive benefit from amnioinfusion were much smaller than his.
His study was conducted in 56 different centers in 13 countries, including South Africa, Canada, and the United States, with the majority of patients enrolled in South Africa. There was no significant difference in results obtained from the various countries, Dr. Fraser said.
The study participants were at greater than 36 weeks' gestation and were stratified for randomization to one of two groups: one group with fetal heart-rate decelerations and one without decelerations. There was no significant difference in results between these two groups.
The investigators also saw a slight trend toward cesarean delivery in the group that received amnioinfusion (32% versus 29%), Dr. Fraser noted.